[vsnet-newvar 1358] (fwd) TYC 5819-01190-1 (Re: News from VSNET) by Jeff Lackmeyer

[Taichi Kato <tkato@kusastro.kyoto-u.ac.jp>]

(fwd) TYC 5819-01190-1 (Re: News from VSNET) by Jeff Lackmeyer

From: "Jeff Lackmeyer" <jllastro@bellsouth.net>
Subject: Re: AstroAlert: News from VSNET
Date: Fri, 21 Dec 2001 12:00:31 -0500

I am not a variable star observer but I do find the subject fascinating.
Last night, I was video taping the graze occultation of Tau Aqr.  Some
minutes before the graze, I imaged the total occultation of its companion,
TYC 5819-01190-1.  I  was not expecting to be able to image this star,
because I have previously determined that video system has a limiting
magnitude of 9.0, and the information  had  ahead of time was a Tycho 1
magnitude of 10.34.  In this case, the star was visible while in direct
contact with the earthlit limb of the Moon.  Since then I found a WDS 1996
magnitude of 9.8.  I also looked up the Tycho 2 values, Bt=11.403, Vt=9.940,
using a formula on the Astrometric Catalog Server web site, that converts to
a Johnson V magnitude of 9.8 which agrees with the WDS 1996 value.

In the references that I have checked, I have not seen where this star has
been identified as a known variable, but there does seem to be some
significant differences between Tycho 1 and 2.  Is this star a known
variable?  What is its range of variability.  Considering that there is no
chance that my video system, which exhibits a pronounced cut off near its
limit, could have captured a star at the listed magnitudes, could this star
be especially bright at the moment?

Jeff Lackmeyer

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